Transcatheter valve with paravalvular leak sealing ring

ABSTRACT

A prosthetic heart valve includes a collapsible and expandable stent extending from an inflow end to an outflow end and a plurality of prosthetic valve leaflets coupled to the stent. The prosthetic heart valve may also include a sealing ring coupled to the inflow end of the stent, the sealing ring comprising a tube extending circumferentially around the inflow end of the stent. The tube may be formed from a wire coiled into a repeating shape, such as a rectangle or a diamond, so that the tube is collapsible. A covering may at least partially surround the tube. The sealing ring may include a first filler positioned within the tube and/or a second filler positioned between the tube and the covering.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/586,595 filed May 4, 2017, which is a continuation of U.S. Pat. No.9,668,858 filed May 12, 2015, which claims the benefit of the filingdate of U.S. Provisional Patent Application No. 61/994,253, filed May16, 2014, the disclosures of which are all hereby incorporated byreference herein.

BACKGROUND

The present disclosure relates to heart valve replacement and, inparticular, to collapsible prosthetic heart valves. More particularly,the present disclosure relates to collapsible prosthetic transcatheterheart valves which minimize or reduce paravalvular leaks.

Prosthetic heart valves that are collapsible to a relatively smallcircumferential size can be delivered into a patient less invasivelythan valves that are not collapsible. For example, a collapsible valvemay be delivered into a patient via a tube-like delivery apparatus suchas a catheter, a trocar, a laparoscopic instrument, or the like. Thiscollapsibility can avoid the need for a more invasive procedure such asfull open-chest, open-heart surgery.

Collapsible prosthetic heart valves typically take the form of a valvestructure mounted on a stent. There are two common types of stents onwhich the valve structures are ordinarily mounted: a self-expandingstent and a balloon-expandable stent. To place such valves into adelivery apparatus and ultimately into a patient, the valve is firstcollapsed or crimped to reduce its circumferential size.

When a collapsed prosthetic valve has reached the desired implant sitein the patient (e.g., at or near the annulus of the patient's heartvalve that is to be replaced by the prosthetic valve), the prostheticvalve can be deployed or released from the delivery apparatus andre-expanded to full operating size. For balloon-expandable valves, thisgenerally involves releasing the valve, assuring its proper location,and then expanding a balloon positioned within the valve stent. Forself-expanding valves, on the other hand, the stent automaticallyexpands as a sheath covering the valve is withdrawn.

After implantation, imperfect sealing between the cuff and the site ofimplant may cause complications such as paravalvular leakage (“PVleak”), or blood flowing through a channel between the structure of theimplanted valve and cardiac tissue as a result of the imperfect sealing.

BRIEF SUMMARY

According to an embodiment of the disclosure a prosthetic heart valveincludes a collapsible and expandable stent extending from an inflow endto an outflow end, and a plurality of prosthetic valve leaflets coupledto the stent. Each leaflet may have a leaflet belly. The prostheticheart valve may include a sealing ring coupled to the inflow end of thestent, the sealing ring comprising a tube extending circumferentiallyaround the inflow end of the stent, wherein the tube is formed from awire coiled into a repeating shape such that the tube is collapsible.The sealing ring may be axially offset from the leaflet belly when thestent is in a collapsed condition.

According to another embodiment of the disclosure, a prosthetic heartvalve includes a collapsible and expandable stent extending from aninflow end to an outflow end and a plurality of prosthetic valveleaflets coupled to the stent. Each leaflet may have a leaflet belly.The prosthetic heart valve may include a sealing ring coupled to theinflow end of the stent, the sealing ring comprising a tube extendingcircumferentially around the inflow end of the stent, a covering atleast partially surrounding the tube, and at least one of a first fillerpositioned within the tube and a second filler positioned between thetube and the covering. The sealing ring may be axially offset from theleaflet belly when the stent is in a collapsed condition.

According to a further embodiment of the disclosure, a prosthetic heartvalve includes a collapsible and expandable stent extending from aninflow end to an outflow end and a plurality of prosthetic valveleaflets coupled to the stent. Each leaflet may have a leaflet belly.The prosthetic heart valve may also include a sealing ring coupled tothe inflow end of the stent, the sealing ring comprising a tubeextending circumferentially around the inflow end of the stent and acovering at least partially surrounding the tube, wherein the coveringhas a first end and a second end, the first end coupled to the stent bya first thread. The sealing ring may be axially offset from the leafletbelly when the stent is in a collapsed condition.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed prosthetic heart valvemay be more fully understood with reference to the following detaileddescription when read with the accompanying drawings, in which:

FIG. 1 is a front view of a collapsible prosthetic heart valve accordingto the prior art;

FIG. 2 is a top cross-sectional view of the prosthetic heart valve ofFIG. 1 implanted in a patient taken along line 2-2;

FIG. 3A is a highly schematic side view of one embodiment of a heartvalve having a sealing ring intended to fill irregularities between theheart valve and the native valve annulus;

FIG. 3B is a highly schematic cross-sectional view of the sealing ringof FIG. 3A;

FIG. 3C is a highly schematic side view of the heart valve of FIG. 3Aimplanted into a native valve annulus with unresected native valveleaflets;

FIG. 3D is a highly schematic side view of the heart valve of FIG. 3Aimplanted into a native valve annulus with resected native valveleaflets;

FIG. 4A is a front view of a rectangular coil of a sealing ring;

FIG. 4B is a front view of a diamond coil of a sealing ring;

FIGS. 5A-5F are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring comprising a tube and acovering;

FIGS. 6A-D are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring comprising a tube, acovering, and an outer filler;

FIGS. 6E-H are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring comprising a tube, acovering, an outer filler, and an inner filler;

FIGS. 6I-N are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring comprising a tube, acovering, and an inner filler;

FIGS. 6O is a highly schematic cross sectional view of a portion of aprosthetic heart valve with a sealing ring comprising a tube and aninner filler;

FIGS. 7A-P are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring having a tacking stitch;

FIGS. 8A-P are highly schematic cross sectional views of a portion of aprosthetic heart valve with a sealing ring having an expandable stitch;and

FIGS. 9A-E illustrate a prosthetic heart valve at different stages ofresheathing into a delivery device.

DETAILED DESCRIPTION

As used herein, the term “inflow end,” when used in connection with aprosthetic heart valve, refers to the end of the heart valve throughwhich blood enters when the valve is functioning as intended. The term“outflow end,” when used in connection with a prosthetic heart valve,refers to the end of the heart valve through which blood exits when thevalve is functioning as intended. As used herein, the terms “generally,”“substantially,” and “about” are intended to mean that slight deviationsfrom absolute are included within the scope of the term so modified.Like numbers refer to similar or identical elements throughout. Whenused herein in the context of a prosthetic heart valve, or a componentthereof, the lengthwise or axial direction refers to a direction along alongitudinal axis passing through the center of the stent or heartvalve. When used herein in the context of a prosthetic heart valve, or acomponent thereof, the circumferential direction refers to a directionextending along the circumference of the prosthetic heart valve.

The sealing portions of the present disclosure may be used in connectionwith collapsible prosthetic heart valves. FIG. 1 shows one suchcollapsible stent-supported prosthetic heart valve 100 in an expandedcondition. The prosthetic heart valve 100 is designed to replace thefunction of a native aortic valve of a patient. The prosthetic heartvalve 100 includes a stent constructed as a frame 102. The stent 102extends in a lengthwise or axial direction L from an inflow or annulusend 130 to an outflow or aortic end 132, and includes an annulus section104 adjacent the inflow end 130 and an aortic section 142 adjacent theoutflow end 132. The annulus section 104 has a relatively small crosssection in the expanded condition, while the aortic section 142 has arelatively large cross section in the expanded condition. The annulussection 104 may be in the form of a cylinder having a substantiallyconstant diameter along its length. A transition section 141 may taperoutwardly from the annulus section 104 to the aortic section 142. Eachof the sections of the stent 102 includes a plurality of cells 112connected to one another in one or more annular rows around the stent102. For example, as shown in FIG. 1, the annulus section 104 may havetwo annular rows of complete cells 112 and the aortic section 142 andthe transition section 141 may each have one or more annular rows ofcomplete or partial cells 112. The cells 112 in the aortic section 142may be larger than the cells 112 in the annulus section 104. The largercells 112 in the aortic section 142 may better enable the prostheticvalve 100 to be positioned without the stent structure 102 interferingwith blood flow to the coronary arteries. At least partly due to theshape of cells 112, the stent 102 elongates in the lengthwise directionL as cells 112 collapse when the stent 102 is transitioned from theexpanded condition to the collapsed condition.

The stent 102 may include one or more retaining elements 118 at theoutflow end 132, the retaining elements 118 being sized and shaped tocooperate with retaining structures provided on a deployment device (notshown). The engagement of the retaining elements 118 with the retainingstructures on the deployment device may help maintain the prostheticheart valve 100 in assembled relationship with the deployment device,minimize longitudinal movement of the prosthetic heart valve relative tothe deployment device during unsheathing or resheathing procedures, andhelp prevent rotation of the prosthetic heart valve relative to thedeployment device as the deployment device is advanced to the targetlocation and during deployment. One such deployment device is shown inU.S. Patent Publication No. 2012/0078352, the entire contents of whichare hereby incorporated by reference herein.

The stent 102 may also include a plurality of commissure points 116 formounting the commissures (not identified) of the valve assemblydiscussed below to the stent 102. As can be seen in FIG. 1, thecommissure points 116 may lay at the intersection of four cells 112, twoof the cells 112 being adjacent one another in the same annular row, andthe other two cells 112 being in different annular rows and lying in endto end relationship. The commissure points 116 may be positionedentirely within the annulus section 104 or at the juncture of annulussection 104 and the transition section 141. The commissure points 116may include one or more eyelets which facilitate the suturing of theleaflet commissure to the stent.

The prosthetic heart valve 100 includes a valve assembly 140 positionedin the annulus section 104. In the particular embodiment depicted, thevalve assembly includes three leaflets 108. Two leaflets join oneanother at each of three commissures. When implanted at the nativeaortic valve annulus, blood flows from the inflow end 130, past leaflets108, and toward the outflow end 132. This occurs when pressure in theleft ventricle is greater than the pressure in the aorta, forcing theleaflets 108 to open. When pressure in the aorta is greater thanpressure in the left ventricle, the leaflets 108 are forced closed andcoapt with one another along free edges of the leaflet 108, blockingblood from flowing in a retrograde fashion from the outflow end 132 tothe inflow end 130. The valve assembly 140 may be mounted to the stent102 by suturing the commissures of the leaflets 108 to the commissurepoints 116 and suturing other portions of the valve assembly 140 to thestent 102, or by other methods known in the art. The valve assembly 140may include a cuff 106 and a plurality of leaflets 108 whichcollectively function as a one way valve by coapting with one another.FIG. 1 illustrates a prosthetic heart valve for replacing a nativetricuspid valve, such as the aortic valve. Accordingly, the prostheticheart valve 100 is shown in FIG. 1 with three leaflets 108, as well asthree commissure points 116. However, it will be appreciated that theprosthetic heart valves according to aspects of the disclosure may havea greater or lesser number of leaflets 108 and commissure points 116.

The leaflets 108 may define a leaflet belly B, indicated with brokenlines in FIG. 1. The leaflet belly B is the portions of valve assembly140 above which leaflets 108 are free to move radially inwardly to coaptwith one another along their free edges. With this configuration, thevalve assembly 140 is particularly thick at points at or above leafletbelly B. As such, any additional material axially aligned with valveassembly 140 above (or distal to) leaflet belly B may add significantlyto the crimp profile of the valve 100.

Although the cuff 106 is shown in FIG. 1 as being disposed on thelumenal or inner surface of the annulus section 104, the cuff 106 may bedisposed on the ablumenal or outer surface of annulus section 104, ormay cover all or part of either or both of the lumenal and ablumenalsurfaces of the annulus section 104. As is shown in FIG. 1, in oneexample the entirety of the valve assembly 140, including the leafletcommissures, is positioned in the annulus section 104 of the stent 102.When opened, the leaflets may extend further into the transition region141 or may be designed such that they remain substantially completelywithin the annulus region 104. In this embodiment, substantially theentirety of the valve assembly 140 is positioned between the proximalend 130 of stent 102 and the commissure points 116, and none of thevalve assembly is positioned between the commissure points 116 and thedistal end 132 of the stent 102.

In operation, the embodiments of the prosthetic heart valve 100described above may be used to replace a native heart valve, such as theaortic valve, a surgical heart valve, or a heart valve that hasundergone a surgical procedure. The prosthetic heart valve 100 may bedelivered to the desired site (e.g., near a native aortic annulus) usingany suitable delivery device. During delivery, the prosthetic heartvalve 100 is disposed inside the delivery device in the collapsedcondition. The delivery device may be introduced into a patient usingany known procedures, such as a transfemoral, transapical, ortransseptal approach. Once the delivery device has reached the targetsite, the user may deploy the prosthetic heart valve 100. Upondeployment, the prosthetic heart valve 100 expands into secureengagement within the native aortic annulus. When the prosthetic heartvalve 100 is properly positioned inside the heart, it works as a one-wayvalve, allowing blood to flow in one direction and preventing blood fromflowing in the opposite direction.

FIG. 2 is a highly schematic cross-sectional illustration of theprosthetic heart valve 100 having leaflets 108 disposed within thenative valve annulus 250, taken along line 2-2 shown in FIG. 1. As seenin FIG. 2, the substantially circular annulus section 104 of the stent102 is disposed within a non-circular native valve annulus 250. Atcertain locations around the perimeter of the prosthetic heart valve100, gaps 200 form between the heart valve 100 and the native valveannulus 250. Blood flowing through these gaps and around the valveassembly 140 of the prosthetic heart valve 100 can result in PV leak orregurgitation and other inefficiencies which can reduce cardiacperformance. Such improper fitment may be due to suboptimal native valveannulus geometry due, for example, to calcification of the native valveannulus 250 or due to unresected native leaflets.

FIG. 3A illustrates a heart valve 300 according to one embodiment of thedisclosure intended to reduce the likelihood and severity of PV leakbetween the heart valve and a native valve annulus. Heart valve 300 mayhave a stent 302 which extends between inflow end 330 and outflow end332, a valve assembly 340 having a plurality of leaflets 308, and a cuff306. Heart valve 300 may be formed of any of the materials and in any ofthe configurations described above with reference to FIG. 1.

The stent 302 may be wholly or partly formed of any biocompatiblematerial, such as metals, synthetic polymers, or biopolymers capable offunctioning as a stent. Suitable biopolymers include, but are notlimited to, elastin, and mixtures or composites thereof. Suitable metalsinclude, but are not limited to, titanium, nickel, stainless steel, andalloys thereof, including nitinol. Other metals that have elastic and/ormemory properties may also be suitable, such as spring stainless steel,trade named alloys such as Elgiloy®, and Hastelloy®, CoCrNi alloys(e.g., trade name Phynox), MP35N®, CoCrMo alloys, mixtures of suchalloys or mixtures of metal and polymer fibers. Suitable syntheticpolymers for use as a stent include, but are not limited to,thermoplastics, such as polyolefins, polyesters, polyamides,polysulfones, acrylics, polyacrylonitriles, polyetheretherketone (PEEK),and polyaramides. Furthermore, the stent 302 need not be cylindricallyshaped. For example, stent 302 may take the shape of an ellipse or othershapes, such as a general “D” shape with a substantially straightsection and an arcuate section extending from one end of the straightsection to the other. Such a “D” shape may better conform to particularanatomies, such as the mitral valve, the tricuspid valve, or a diseasedbicuspid valve. Other portions of the valve, such as the sealing ring350, described in greater detail below, may take similar shapes, forexample depending on the stent 302 on which they are positioned.

The valve assembly 340 may be wholly or partly formed of any suitablebiological material or polymer. Examples of biological materialssuitable for the valve assembly 340 include, but are not limited to,porcine or bovine pericardial tissue. Examples of polymers suitable forthe valve assembly 340 include, but are not limited to, polyurethane,silicone, PTFE, and polyester. In at least some examples, portions ofvalve assembly 340, a cuff and the suture used may include an ultra-highmolecular weight polyethylene. An example of one such valve assembly 340is disclosed in U.S. Patent Publication No. 2010/0185277, the entirecontents of which are hereby incorporated by reference herein. Althoughvalve assembly 340 typically includes one or more leaflets, othersuitable valve assemblies without leaflets that work as one-way valvesmay be alternately used.

Similar to cuff 106, cuff 306 may be disposed on the lumenal side ofstent 302, the ablumenal side of stent 302, or both. Both the cuff 306and the leaflets 308 may be wholly or partly formed of any suitablebiological material or polymer, including those, such as PTFE, describedabove in connection with the prosthetic heart valve 300. Additionally,the cuff 306 may be formed from polyurethane copolymers or includeultra-high molecular weight polyethylene.

It should be noted that while the disclosure herein is predominatelydiscussed in terms of a tricuspid valve, i.e., a valve having threedistinct mutually coapting leaflets, and a stent having a shape asillustrated in FIG. 3A, the valve and stent may take other forms. Forexample, the valve could be a bicuspid valve, i.e., a valve having twocoapting leaflets, or other types of valves, including valves withgreater or fewer leaflets as well as non-leaflet valves. Similarly, thestent could have different shapes, such as a flared or conical annulussection, a more or less bulbous aortic section, a differently shapedtransition section between the aortic section and the annulus section,any other suitable shape, and may or may not be collapsible.

Heart valve 300 may include a sealing element, such as sealing ring 350,at or near inflow end 330 of stent 302 to help mitigate PV leak, asillustrated in FIG. 3A. FIG. 3B illustrates an enlarged cross-sectionalview of sealing ring 350 taken along a cutting plane P transverse to thecircumferential direction of sealing ring 350. Generally, sealing ring350 may comprise tube 400 with or without a covering 500, with optionalouter filler 610 between the covering 500 and the tube 400, and withoptional inner filler 620 inside the tube 400. Unless stated otherwise,the term filler, as used herein, refers to the outer filler 610 and/orthe inner filler 620. Sealing ring 350 may include any combination oftube 400, covering 500, and filler. If outer filler 610 is used,covering 500 may be required to contain outer filler 610 within sealingring 350. Prior to describing sealing ring 350 in greater detail, thefunction of sealing ring 350 is briefly explained.

FIGS. 3C-D illustrate heart valve 300 disposed within a native valveannulus 250 adjacent unresected native leaflets 203 and adjacentresected leaflets, respectively. When implanted within native valveannulus 250, sealing ring 350 may be disposed, for example, below thenative valve annulus 250 (i.e., in a sub-annular position) or belownative leaflets 203 (i.e., in a sub-leaflet position). As shown in FIG.3C, sealing ring 350 is disposed such that it is in contact with theleft ventricular outflow tract (“LVOT”) 204, although it may be disposedwithin the native annulus 250, or at the juncture between native annulus250 and LVOT 204. Such positioning helps to provide a seal between heartvalve 300 and the native heart tissue. For example, as illustrated inFIG. 3D, despite gaps 200 between heart valve 300 and native valveannulus 250, sealing ring 350 helps prevent retrograde blood flow aroundthe outer circumference of valve 300. Sealing ring 350 may additionallyhelp prevent heart valve 300 from migrating into the aorta whenimplanted at the native aortic valve annulus. It should be noted thatthe sealing ring 350 may be flexible such that it conforms to thegeometry in which it is positioned. For example, sealing ring 350 mayconform to the LVOT 204, native annulus 250, or any other structure to agreater degree than illustrated in FIG. 3C. Also, as should beunderstood, sealing ring 350 may be positioned below the native annulus250, at the native annulus 250, above the native annulus 250, or anycombination thereof, for example being in contact with the nativeannulus 250 and extending slightly below the native annulus 250 as well.

As noted above, sealing ring 350 may include elements such as tube 400,covering 500, and filler material. Generally, tube 400 may provide astructural support onto which covering 500 may be attached and intowhich outer filler 610 or inner filler 620 may be inserted. Tube 400alone may provide sealing of prosthetic valve 300, although such sealingmay be enhanced with the addition of covering 500 and/or filler.

While the intent of sealing ring 350 is to mitigate and/or prevent PVleak, there is generally a correlation between the amount of materialforming valve 300 and the size of the valve when crimped to a collapsedcondition. When using a collapsible and expandable prosthetic valve,such as valve 300, the valve 300 is generally crimped into a collapsedcondition for loading within a sheath of a delivery device that isdelivered through the body, such as through the vasculature, to the siteof implantation. As such, a large crimp profile for valve 300 generallyrequires the delivery device to incorporate a correspondingly largediameter sheath. As used herein, the term “crimp profile” generallyrefers to the largest diameter of a prosthetic valve when it is in acollapsed condition. A large diameter delivery system may be incapableof being passed through the patient's vasculature, while a deliverysystem having a smaller diameter and housing a heart valve with asmaller crimp profile may be easier to navigate through the patient'sbody and may also reduce the operation time.

As illustrated in FIGS. 3A, 3C, and 3D, sealing ring 350 may be attachedto inflow end 330 of valve 300. In particular, sealing ring 350 may bepositioned such that it does not overlap in the axial direction, or onlyminimally overlaps, the region of the valve having prosthetic leaflets308 when the prosthetic heart valve 300 is in the collapsed condition.In particular, the sealing ring 350 may be axially offset from the bellyregions of the prosthetic leaflets 308. There may also be little or noaxial overlap when the prosthetic heart valve 300 is in the expandedcondition, as shown in FIGS. 3A, 3C and 3D. As used herein, “axialoverlap” refers to portions of two structures being within the sameradial line extending perpendicularly from the lengthwise direction L.With this configuration, when prosthetic valve 300 is crimped into acollapsed condition, such as for loading onto a delivery device, thereis little or no axial overlap between sealing ring 350 and the region ofvalve 300 at which prosthetic leaflets 308 are positioned. As a result,valve 300 may have a smaller crimp profile compared to anotherprosthetic valve having the same sealing ring located closer toward theregion at which prosthetic leaflets 308 are positioned.

In one example, sealing ring 350 is positioned such that approximatelyhalf of the sealing ring is positioned above (i.e. circumferentiallyoverlapping) the stent 302 at its inflow end 330 and approximately halfof the sealing ring is positioned below (i.e. not circumferentiallyoverlapping) the stent at its inflow end when valve 300 is in theexpanded condition. In another example, sealing ring 350 may be nearlycompletely positioned below the stent 302 at its inflow end 330 whenvalve 300 is in the expanded condition. In a further example, theproximalmost end of the sealing ring 350 may substantially align withthe proximal most portion of the inflow end 330 of the stent 302 whenvalve 300 is in the expanded condition. When used herein in the contextof a prosthetic heart valve, the term proximal refers to a directioncloser to the inflow end of the valve, while the term distal refers to adirection closer to the outflow end of the valve.

In addition to the positioning of sealing ring 350 with respect to othercomponents of valve 300, the material and structure of the components ofsealing ring 350 may have an effect on the effectiveness of mitigatingPV leak while maintaining a relatively small crimp profile.

Tube 400 of sealing ring 350 may be formed of various materials. Inaddition, the material forming tube 400 may have one or more of avariety of structures. For example, the material of tube 400 may beindividual strands braided into a generally tubular mesh structure, ormay be an individual strand formed into a coil. For a braided tube 400,the strands forming the braid may have a particular relative orientationwith respect to one another (e.g., a helical braid).

Covering 500 may be formed of one or more materials having lowpermeability or no permeability to water and/or blood. For example,covering 500 may be formed of tissue, including but not limited topericardium or other sheet-like tissue obtained from animals or bytissue engineering. The covering 500 may be formed of a fabric-typematerial, such as a fabric formed of polytetrafluoroethylene (PTFE),polyethylene terephthalate (PET), or ultra-high molecular weightpolyethylene (UHMWPE). The covering 500 may also be formed of syntheticor natural polymers, such as silicones, polyvinyl alcohol (PVA), orcollagen sheets. The covering 500 may be formed of any one or anycombination of the above-listed materials.

The filler may be formed of any of a variety of materials. For example,the filler may be composed of the same material described in connectionwith tube 400, such as a coil or mesh braid formed of Nitinol. Thefiller may also be composed of any material described in connection withcovering 500, such as fabrics, tissues, and synthetic or naturalpolymers. Furthermore, the filler may be composed of a water swellablematerial, such natural sea sponge or beads, or other materials thatexpand upon exposure to body conditions. This may include, for example,PVA microspheres that expand upon contact with blood. Other materialsthat expand after exposure to temperatures found in the body orcomponents of the blood may also be suitable for the filler. Anotherpotential material for filler is a highly compressible sponge, forexample one made from alginate cross-linked at low temperatures. Such ahighly compressible sponge may collapse to a large extent when shearforces are applied, while being able to return to an original shape uponremoval of the forces. Such a property may contribute to a smaller valvecrimp profile while retaining the ability to “spring back” to anoriginal shape upon deployment of the valve. Further, a single fillercomposed of a single material or a combination of materials describedabove may be used, or multiple fillers each composed of one or acombination of any of the above materials may be used.

In one embodiment, prosthetic valve 300 may include sealing ring 350that includes tube 400 formed of braided mesh of a shape-memorymaterial, of a super-elastic material, of a bio-compatible polymer, orof another material that is capable of being collapsed and expanded intoa desired shapes. Generally, tube 400 takes the shape of a hollowannulus wrapped around a portion of stent 302, such that tube 400generally forms a hollow torus. It should be understood that tube 400need not meet the precise mathematical definition of a torus or othertoroid. Tube 400 may comprise a braided metal fabric that is bothresilient and capable of heat treatment to substantially set a desiredshape, such as Nitinol, or any other metal suitable for use of stent 302described above. However, it should be understood that other materials,such as braided polymers, including polypropylene, may be used for thebraided mesh version of tube 400. Depending on the individual materialselected, the strand diameter, number of strands, and pitch may bealtered to achieve the desired properties for tube 400. If sealing ring400 comprises only braided mesh, the braided tube 400 may help inreducing PV leak, for example by creating a seal as blood clots form inthe braid. PV leak may be further mitigated to the extent tissuein-growth occurs on the sealing ring 350, such as by endothelializationand/or epithelialization. Such sealing by clotting and/or thrombusformation may take up to an hour or more to form, with tissue in-growthoccurring over a longer time. However, faster sealing may be a desirableresult. For example, faster sealing may provide a physician withimmediate or near immediate feedback that PV leak is not occurring atunacceptable levels, regardless of the fact that PV leak may beappropriately mitigated given the amount of time required for clottingin the braided tube 400. As is described in greater detail below, acovering 500 and/or filler may be used in combination with a braidedtube 400 (or a coiled tube 400 as described below) to accelerate sealingand enhance tissue in-growth.

One of the advantages of using braided Nitinol for tube 400 is that thestructure relatively easily undergoes a transition into differentshapes. For example, it may be easily collapsible for delivery, easilyexpandable upon implantation, and may change shape as appropriate tofill in gaps 200 in native annulus 250. However, as noted above, it maybe desirable to add a covering 500 and/or filler if tube 400 is formedof braided mesh. The addition of such material may change the way thebraided mesh changes shapes. For example, if the braid is coveredtightly with a covering 500, the braid may not behave the same as itwould without such a covering. One possible solution to this challengeis the choice of material for covering 500 and/or filler material, aswell as the way the covering 500 is attached to tube 400, which isdescribed in greater detail below. Another possible solution is to use adifferent structure for tube 400.

Instead of forming tube 400 of a braided mesh, it may be desirable toform tube 400 from a coiled material, such as coiled Nitinol (or anyother material suitable for use in forming stent 302). In particular,tube 400 may be formed of a single strand of material, or single standsof material attached end-to-end, coiled into a desired shape. Forexample, tube 400 may be formed of a strand of Nitinol coiled into acircular shape, a rectangular shape, or a diamond shape. The strand ofmaterial forming the coil may have various cross-sectional shapes, suchas round, flat (e.g. a ribbon), or rectangular. Still further, thecoiled wire may take the form of a coil, multiple wires wound togetherin different directions (e.g., a braid), two or more wires woundtogether in the same direction (e.g., two wires wound as a doublehelix). The coiled wire may be later cut from a tube and may havevarying diameters along the length of the coil. In addition, the coilneed not be a closed coil, but may be an open coil having, for example,a “U” or “C” shape.

Generally, tube 400 may have different qualities when formed from a coilcompared to a braided mesh. For example, a tube 400 formed from a coilmay collapse to a smaller profile than a similar tube formed of abraided mesh. On the other hand, if sealing ring 350 is formed solely oftube 400 comprising a coil, sealing via clotting may be slower or maynever occur at all compared to the braided mesh version. But when acovering 500 and/or filler is included with a tube 400 formed of a coil,the sealing ring 350 may seal against PV leak rapidly. However, itshould be clear that a covering 500 and/or filler may similarly be usedin conjunction with a braided mesh version of tube 400.

As noted above, when tube 400 is formed of a coil, the coil may takedifferent general shapes, such as that of a circle (not illustrated), ofa rectangle (FIG. 4A), or a diamond (FIG. 4B). The coils shown in FIG.4A-B are viewed along the same cutting plane P shown in FIG. 3B. Assuch, multiple turns or iterations of each coil shape are visible inFIGS. 4A-B. Stated more precisely, the shape of the coil is a rectangle(FIG. 4A) or a diamond (FIG. 4B) when an individual turn of the coiledwire is projected onto a plane. The use of a rectangular coil 410 ordiamond coil 420 for tube 400 may have an advantage in that therespective coils are more readily collapsible than, for example, acircular coil or braided mesh. In particular, the corners 415 ofrectangular coil 410 and the peaks 425 of diamond coil 420 facilitatethe respective coils collapsing during loading, delivery, and/orresheathing of valve 400. Benefits of the tube 400 being readilycollapsible may include a reduced overall delivery profile, as well therequirement of relatively little force to load and/or resheathprosthetic valve 300 prior to being fully released in the native annulus250. It should be noted that rectangular coil 410 is shown in FIG. 4A(and diamond coil 420 in FIG. 4B) not in the form of tube 400, butrather a segment thereof. In stent 300, rectangular coil 410 or diamondcoil 420 would extend along a circumferential path around inflow end 330of valve 300, forming tube 400. As should be clear from the above, theterm “tube” does not solely refer to an elongated cylindrical structure,as the rectangular coil 410 and diamond coil 420 extendedcircumferentially around stent 300 is still considered herein as a tube400. In fact, although shown throughout this disclosure as a torus, thetube 400 need not be a toroid at all. For example, tube 400 of sealingring may undulate such that points on the proximal (or distal) surfacedo not lie in the same plane as other points on the proximal (or distal)surface. As such sealing ring 350 may have an undulating quality aswell.

Varying the geometry of the shape of the coil may provide for differenteffects in terms of profile and sealing. For example, when using adiamond coil 420, the lengths of the major axis X_(MAJOR) and minor axisX_(MINOR) may be, respectively, approximately 3 mm by approximately 2mm, approximately 4 mm by approximately 2 mm, or approximately 4 mm byapproximately 3 mm. The lengths of the major and minor axes should beunderstood to be examples, and not requirements. The examples givenabove may be useful for achieving a bulge in the sealing ring 350 ofapproximately 2-3 mm from the outer circumference of the stent 302,which may be particularly effective at reducing PV leak. Further, asnoted above, wires having cross-sections other than circular, includingflat and/or rectangular, may be used to form coil tube 400. Generally,the goal is to decrease the collapsed profile of the valve 300 includingsealing ring 350, while retaining enough strength within the sealingring 350 to push or abut against the native valve annulus 250 toeliminate or reduce any gaps 200 between the native valve annulus 250and the prosthetic valve 300. While the thickness of the coil formingtube 400 may vary in size, particularly depending upon the shape of thecoil, one exemplary range of thicknesses is between approximately 0.05mm and approximately 0.175 mm The term thickness in the context of acoiled wire refers to a cross-sectional dimension of the wire. Forexample, a coil having a circular cross-section has a thickness equal tothe diameter of the cross-section. It should be noted that the abovedimensions provided in relation to components of tube 400, as well asany other dimensions provided herein, are for illustrative purposes.Varying dimensions may be used without departing from the scope of thisdisclosure.

Other features of the braids and/or coiled wires forming tube 400 may bemodified and optimized to achieve a better seal against PV leak,including, for example, the wire or braid density, shape, and stiffness.Also, when tube 400 is formed of a coiled wire, the ratio of thicknessof the coil to the spacing between adjacent iterative shapes of the coil(i.e., pitch) may have an effect on PV leak sealing. For example, arelatively large pitch may lead to kinking or tenting (i.e., a deviationfrom a smooth circumference) in the tube 400, which may reduce theeffectiveness of sealing against PV leak. In some embodiments, it may bepreferable that the ratio of coil thickness to the pitch is betweenapproximately 1:6 and approximately 1:32.

As noted above, when tube 400 is formed of a coiled material, ratherthan a braided mesh, it may be advantageous to include a covering 500that at least partially surrounds tube 400. It may also be advantageousto include a filler material inside and/or outside the tube 400.However, it should be understood that a covering 500 and filler may beused regardless of whether tube 400 is formed of a coil or a braidedmesh. For example, if tube 400 is formed of either a metallic coil or ametallic braided mesh, a covering 500 may be desired to reduce thelikelihood and/or severity of abrasion from metal-on-metal contactbetween tube 400 and stent 302.

FIGS. 5A-F are highly schematic cross-sectional drawings of an inflowportion 330 of valve 300 with a sealing ring 350 taken along the samecutting plane P illustrated in FIG. 3B. In these embodiments, sealingring 350 comprises tube 400 and covering 500. In particular, tube 400may take any form described above, such as a braided mesh or coil. Theaddition of covering 500 to tube 400, in particular a covering 500 withlow or no permeability to water and/or blood, may facilitate creating abetter seal between sealing ring 350 and the native valve annulus 250.In addition to physically blocking blood from flowing past the sealingring 350, covering 500 may accelerate clotting within sealing ring 350to the extent clotting occurs, and may further facilitate tissueingrowth to create a better seal over time. Although some materials mayhave greater porosity than others, and thus greater permeability towater, those materials may be advantageous if, for example, they haverelatively small thickness, relatively good tissue ingrowth, or otherproperties that help reduce the crimp profile of sealing ring 350 withvalve 300.

Each embodiment of sealing ring 350 shown in FIGS. 5A-5F includes tube400, covering 500, and one or more connections 510 connecting covering500 to tube 400 and/or the stent 302 of valve 300. It should be notedthat although connections 510 are described as being connected to thestent 302, connections may alternatively be connected to other portionsof the prosthetic heart valve 300, such as the cuff 306, in addition oralternatively to the stent 302. Connections may be, for example, suturesor other strand-like material. Various stitch patterns, such as runningstitches and whip stitches, may be used for connections 510. It shouldfurther be noted that, although tube 400 is generally described as beingconnected to valve 300 with stitching and/or sutures, other methods ofconnection, including welding, adhesives, etc. may be suitable inaddition or in the alternative to stitching.

In FIG. 5A, one edge of covering 500 is stitched to stent 302, tube 400is stitched to stent 302, and covering 500 does not surround the entirecross-section of tube 400. In FIG. 5B, one stitch 510 connects a firstedge of covering 500 to stent 302, another stitch 510 connects the otheredge of covering 500 to tube 400, and covering 500 does not surround theentire cross-section of tube 400. In FIG. 5C, one edge of covering 500is connected to both stent 302 and tube 400 by a single stitch 510, andthe covering 500 does not surround the entire cross-section of tube 400.In FIG. 5D, one edge of covering 500 is connected to both stent 302 andtube 400 with a first stitch 510, the other edge of covering 500 isconnected to tube 400 with a second stitch 510, and the covering 500does not cover the entire cross-section of tube 400. In FIG. 5E,covering 500 surrounds the entire cross-section of tube 400, and onestitch 510 connects each edge of covering 500 to stent 302. In FIG. 5F,covering 500 surrounds the entire cross-section of tube 400 and onestitch 510 connects each edge of covering 500 to both stent 302 and tube400.

In each of the embodiments described in connection with FIGS. 5A-F, anumber of stitches 510 may be used to connect covering 500 to tube 400and/or stent 302 along the circumference of the inflow end 330 of thestent 302. It should be noted that there may be a benefit of using fewor no sutures attaching covering 500 directly to tube 400. For example,particularly when tube 400 comprises braided Nitinol, tight and/orfrequent stitches 510 connecting covering 500 directly to tube 400 mayreduce the ability of tube 400 to predictably undergo a transition inshape to fill gaps 200 in native valve annulus 250. Additionally,allowing little or no slack between tube 400 and covering 500 mayrestrict the ability of tube 400 to change shape appropriately to fillin any gaps 200 between native valve annulus 250 and prosthetic valve300. For example, the configurations illustrated in FIGS. 5A-D leave aproximal end of tube 400 exposed. If tube 400 is comprised of a wirecoiled in a diamond shape 425, during expansion (or during collapsing),the diamond shape may grow in a lengthwise dimension as the peaks 425 ofthe minor axis X_(MINOR) come together and the peaks 425 of the majoraxis X_(MAJOR) move apart. The exposed proximal end of tube 400 mayfacilitate such change in shape. It should further be noted that,particularly in embodiments in which both edges of covering 500 areconnected to the stent 302 and/or tube 400, the position of the covering500 with respect to the tube 400 may be reversed. Taking the embodimentillustrated in FIG. 5D as an example, the covering 500 may be positionedto surround the proximal end of tube 400 leaving the distal end of tube400 exposed. If the covering 500 takes this reverse position, it may bedesirable to connect the covering to the valve 300 in a way to reducethe possibility of the covering 500 sliding with respect to theconnection point, for example because of the force of gravity. Suchconnection may be made, for example, by attaching the covering 500 to aneyelet, groove, or other structure on stent 302, where the possibilityof such sliding motion is limited. This reverse orientation may beapplicable to remaining embodiments described below.

As should be clear from the above description, covering 500 need notsurround the entire cross-section of tube 400, and may cover only theportion facing the direction of retrograde blood flow when implanted inan intended position. As illustrated in FIGS. 5A-F, this surface of tube400 is oriented on the proximal end of tube 400, facing away from inflowend 330. Using a partial covering 500 may reduce the amount of material,and thus reduce the bulk and profile of valve 300 when in the collapsedcondition, while covering 500 still is in contact with any retrogradeblood flow contacting sealing ring 350. Covering 500 may still contactany retrograde blood flow contacting sealing ring 350 if oriented on thedistal end of tube 400. Similarly, the greater the number of stitches510 used, both in terms of the points of connection of covering 500 totube 400 and stent 302, as well as the frequency of those stitches alongthe length of the circumference of stent 302, may effect the crimpprofile of valve 300. Generally, as more stitches 510 are used, thecrimp profile of valve 300 increases and the covering 500 is moretightly attached to tube 400. Although not described above, othercombinations of stitch locations and configurations of covering 500 withrespect to tube 400 and stent 302 may be suitable.

FIGS. 6A-O are highly schematic cross-sectional drawings of an inflowportion 330 of valve 300 with a sealing ring 350 taken along the samecutting plane P as shown in FIG. 3B. In these embodiments, sealing ring350 comprises tube 400 and filler, with some embodiments also includingcovering 500. In particular, tube 400 may take any form described above,such as a braided mesh or coil. Covering 500, if used, may take anysuitable form, such as those described above. The filler may bepositioned completely or substantially within tube 400 (inner filler620), between tube 400 and covering 500 (outer filler 610, if covering500 is present), or both. The filler may help accelerate sealing againstPV leak, for example by reducing clotting time, particularly if covering500 is permeable to water. As described above in connection with FIGS.5A-F, a variety of stitches 510 and configurations of covering 500 maybe used for sealing ring 350. It should be noted that if the fillertakes the form of a metal or other abrasive material, a buffer material(such as fabric) may be appropriate to include to reduce the possibilitythat the filler will the tube 400 will fret against one another.

Each embodiment of sealing ring 350 shown in FIGS. 6A-6D includes tube400, covering 500, outer filler 610, and one or more connections 510connecting covering 500 and/or outer filler 610 to tube 400 and/or thestent 302 of valve 300. Outer filler 610 refers to filler that ispositioned between tube 400 and covering 500. In FIG. 6A, covering 500surrounds the entire cross-section of tube 400 and one stitch 510connects each edge of covering 500 to the stent 302. Outer filler 610 ispositioned between tube 400 and covering 500 and surrounds thecross-section of tube 400. In FIG. 6B, covering 500 surrounds the entirecross-section of tube 400, and one stitch 510 connects each edge ofcovering 500 to stent 302 and tube 400. Outer filler 610 is positionedbetween tube 400 and covering 500 and surrounds the cross-section oftube 400. In FIG. 6C, one edge of covering 500 is connected to bothstent 302 and tube 400 with a first stitch 510, the other edge ofcovering 500 is connected to tube 400 with a second stitch 510, and thecovering 500 does not cover the entire cross-section of tube 400.Similarly, the outer filler 610 is positioned between tune 400 andcovering 500 and does not surround the entire cross-section of tube 400.In FIG. 6D, one stitch 510 connects a first edge of covering 500 tostent 302, another stitch 510 connects the other edge of covering 500 totube 400, and covering 500 does not surround the entire cross-section oftube 400. Similarly, outer filler 610 is positioned between tube 400 andcovering 500 and does not surround the entire cross-section of tube 400.

FIGS. 6E-H correspond to FIGS. 6A-D, respectively, with the exceptionthat in addition to an outer filler 610, the sealing rings 350 of FIGS.6E-H include an inner filler 620. Inner filler 620 refers to filler thatis positioned substantially or completely within tube 400. Otherwise,the patterns of covering 500 and stitches 510 are identical betweenFIGS. 6A-D and 6E-H, respectively.

FIGS. 6I-L correspond to FIGS. 6E-H, respectively, with the exceptionthat outer filler 610 is absent and only inner filler 620 is present.Otherwise, the patterns of covering 500 and stitches 510 are identicalbetween FIGS. 6E-H and 6I-L, respectively.

In FIG. 6M, one edge of covering 500 is stitched to stent 302, andcovering 500 does not surround the entire cross-section of tube 400.Inner filler 620 is positioned within tube 400. This generallycorresponds to sealing ring 350 of FIG. 5A with an inner filler 620. InFIG. 6N, one edge of covering 500 is connected to both stent 302 andtube 400 by a single stitch 510, and the covering 500 does not surroundthe entire cross-section of tube 400. Inner filler 620 is positionedwithin tube 400. This generally corresponds to sealing ring 350 of FIG.5C with an inner filler 620. In FIG. 6O, covering 500 is absent and asingle stitch 510 attaches tube 400 to stent 300, with inner filler 620positioned within tube 400. In this embodiment, it is important thatinner filler 620 and tube 400 be chosen such that inner filler 620cannot escape tube 400.

As described in connection with sealing rings 350 illustrated in FIGS.5A-F, any covering 500 used in connection with filler may surround theentire cross-section of tube 400 or only a portion thereof. The same istrue of outer filler 610. Further, as described above with reference toFIGS. 5A-F, the orientation of covering 500 may be reversed so that thecovering 500 covers only a distal portion of tube 400. In embodiments inwhich covering 500 has this reverse orientation, outer filler 610 mayalso have a similar reverse orientation.

As described above the tube 400 may not change shapes as expected ifcovering 500 is tightly wrapped around and connected to tube 400. Thismay be particularly true of a tube 400 formed of a braided mesh. One wayof mitigating this potential problem is, as described above, reducing oreliminating the number of stitches 500 directly connecting covering 500to tube 400. However, another solution is the use of tacking stitching520 or expandable stitching 530. Tacking stitching 520, illustrated inFIGS. 7A-P, generally refers to the use of intermittent stitching alongthe circumference of stent 302 holding the stitched material loosely inplace. Expandable stitching 530, illustrated in FIGS. 8A-P, generallyrefers to stitching that allows for seam expansion. Expandable stitching530 may be accomplished, for example, with the use of a very loosestitch or with a stitch sewn with an elastic material, such as threadformed from silicone.

For example, FIGS. 7A-D illustrate sealing ring 350 with covering 500attached at a first edge to stent 302 with a first stitch 510 and at asecond edge to tube 500 with a tacking stitch 520, represented in thefigures by a line with a cross through the line. The covering 500 doesnot fully cover the cross-section of tube 400, nor does the outer filler610, where present. FIGS. 7A-D illustrate embodiments of sealing ring350 with no filler (FIG. 7A), outer filler 610 (FIG. 7B), outer filler610 and inner filler 620 (FIG. 7C), and inner filler 620 (FIG. 7D).

FIGS. 7E-H illustrate sealing ring 350 with covering 500 attached at afirst edge to stent 302 with a stitch 510 and at a second edge to stent302 with a tacking stitch 520. The covering 500 fully covers thecross-section of tube 400, as does the outer filler 610, where present.FIGS. 7E-H illustrate embodiments of sealing ring 350 with no filler(FIG. 7E), outer filler 610 (FIG. 7F), outer filler 610 and inner filler620 (FIG. 7G), and inner filler 620 (FIG. 7H).

FIGS. 7I-L illustrate sealing ring 350 with covering 500 attached at afirst edge to stent 302 and tube 400 with a stitch 510 and at a secondedge to tube 400 with a tacking stitch 520. The covering 500 does notfully cover the cross-section of the tube 400, nor does the outer filler610, where present. FIGS. 7I-L illustrate embodiments of sealing ring350 with no filler (FIG. 71), outer filler 610 (FIG. 7J), outer filler610 and inner filler 620 (FIG. 7K), and inner filler 620 (FIG. 7L).

FIGS. 7M-P illustrate sealing ring 350 with covering 500 attached tostent 302 and tube 400 with a stitch 500, with both edges of covering500 attached to one another and tube 400 with a tacking stitch 520. Thecovering 500 fully covers the cross-section of the tube 400, as does theouter filler 610, where present. FIGS. 7M-P illustrate embodiments ofsealing ring 350 with no filler (FIG. 7M), outer filler 610 (FIG. 7N),outer filler 610 and inner filler 620 (FIG. 7O), and inner filler 620(FIG. 7P).

FIGS. 8A-8P illustrate embodiments of sealing ring 350 using anexpandable stitch 530. FIGS. 8A-D illustrate sealing ring 350 withcovering 500 attached at a first edge to stent 302 with a stitch 510 andat a second edge to tube 500 with an expandable stitch 530, representedin the figures by a line with a zigzag pattern along the line. Thecovering 500 does not fully cover the cross-section of tube 400, nordoes the outer filler 610, where present. FIGS. 8A-D illustrateembodiments of sealing ring 350 with no filler (FIG. 8A), outer filler610 (FIG. 8B), outer filler 610 and inner filler 620 (FIG. 8C), andinner filler 620 (FIG. 8D).

FIGS. 8E-H illustrate sealing ring 350 with covering 500 with anexpandable stitch 530 attaching both edges of the covering 500 to oneanother and the stent 302. The covering 500 fully covers thecross-section of tube 400, as does the outer filler 610, where present.FIGS. 8E-H illustrate embodiments of sealing ring 350 with no filler(FIG. 8E), outer filler 610 (FIG. 8F), outer filler 610 and inner filler620 (FIG. 8G), and inner filler 620 (FIG. 8H).

FIGS. 8I-L illustrate sealing ring 350 with covering 500 attached at afirst edge to stent 302 and tube 400 with a stitch 510 and at a secondedge to tube 400 with an expandable stitch 530. The covering 500 doesnot fully cover the cross-section of the tube 400, nor does the outerfiller 610, where present. FIGS. 8I-L illustrate embodiments of sealingring 350 with no filler (FIG. 8I), outer filler 610 (FIG. 8J), outerfiller 610 and inner filler 620 (FIG. 8K), and inner filler 620 (FIG.8L).

FIGS. 8M-P illustrate sealing ring 350 with covering 500 attached tostent 302 and tube 400 with a stitch 500, with both edges of covering500 attached to one another and tube 400 with an expandable stitch 530.The covering 500 fully covers the cross-section of the tube 400, as doesthe outer filler 610, where present. FIGS. 8M-P illustrate embodimentsof sealing ring 350 with no filler (FIG. 8M), outer filler 610 (FIG.8N), outer filler 610 and inner filler 620 (FIG. 80), and inner filler620 (FIG. 8P).

FIGS. 9A-E illustrate side views of prosthetic heart valve 300 beingresheathed into a delivery device (heart valve 300 only labeled in FIG.9A). Briefly, the delivery device includes an outer sheath 700, a distaltip 710, and an inner sheath 720 (inner sheath 720 labeled only in FIG.9A). In this embodiment, sealing ring 350 takes the form of a tube 400formed of a Nitinol coil with a diamond shape 420. The sealing ring 350is on the left end of the prosthetic valve 300 as illustrated. As notedabove, prosthetic heart valve may be resheathable. For example, duringdelivery, a user may first allow prosthetic heart valve 300 to partiallyexpand outside of outer sheath 700 to test positioning and functioningof the valve (FIG. 9A) prior to fully releasing the valve. FIGS. 7A-Eillustrate different levels of resheathing, with greater resheathingprogressing from FIG. 9A to FIG. 9E. As described above with respect toFIGS. 4A-B, the rectangular shape 410 or diamond shape 420 of a coiledwire forming tube 400 may allow for the tube 400 to collapse to areduced profile during loading or resheathing the valve 300 into thedelivery device. As can be seen in the illustrations, particularly fromFIGS. 9B to FIG. 9D, during loading or resheathing, the tube rectangularshape 410 or diamond shape 420 of the coiled wire may allow the tube 400to fold away from the remainder of valve 300 during the process. Inaddition to collapsing during resheathing (or loading), the sealing ring350, and in particular the tube 400, may pivot or rotate with respect toinflow end 330 of the valve 300. This is best illustrated in FIGS. 9D-E,in which the inflow end 330 enters the outer sheath 700 as the sealingring 350 is forced to pivot or rotate away from the end of distal sheath700. For example, the entirety or nearly the entirety of inflow end 330may be positioned within outer sheath 700 prior to any of sealing ring350 entering outer sheath 700 during a resheathing (or loading) process.As such, when fully loaded into the delivery device, the tube 400 may becompletely or substantially axially offset from the remainder ofprosthetic heart valve 300, including the leaflet belly B regions,reducing the crimping profile even further.

Although certain embodiments of the prosthetic heart valve describedherein may provide a single feature for reducing paravalvular leakage,it should be understood that multiple similar or dissimilar features maybe utilized on a single prosthetic heart valve to reduce paravalvularleak. For example, one or more sealing rings may be used on a singleprosthetic heart valve, including a first sealing ring disposed proximalto (or within) the native valve annulus and a second sealing ringdisposed distal the first sealing ring. In other examples, a sealingring may be disposed proximal to (or within) the native valve annulus,and one or more pockets expandable upon retrograde blood flow may bedisposed distal the sealing ring. Prosthetic heart valves withexpandable pockets are described in greater detail in U.S. PatentPublication No. 2011/0098802, the disclosure of which is herebyincorporated by reference herein.

In one embodiment of the disclosure, a prosthetic heart valve comprises:a collapsible and expandable stent extending from an inflow end to anoutflow end; a plurality of prosthetic valve leaflets coupled to thestent, each leaflet having a leaflet belly; and a sealing ring coupledto the inflow end of the stent, the sealing ring comprising a tubeextending circumferentially around the inflow end of the stent, thesealing ring being axially offset from the leaflet belly when the stentis in a collapsed condition, wherein the tube is formed from a wirecoiled into a repeating shape such that the tube is collapsible; and/or

the wire is coiled into a rectangular shape; and/or

the wire is coiled into a diamond shape having a major axis and a minoraxis; and/or

the major axis is approximately 3 mm and the minor axis is approximately2 mm; and/or

the major axis is approximately 4 mm and the minor axis is approximately2 mm; and/or

the major axis is approximately 4 mm and the minor axis is approximately3 mm; and/or

the wire has a thickness of between approximately 0.05 mm andapproximately 0.175 mm; and/or

the wire has a thickness and there is a distance between adjacentrepeating shapes of the coiled wire, a ratio of the thickness to thedistance being between approximately 1:6 and approximately 1:32.

In another embodiment of the disclosure, a prosthetic heart valvecomprises: a collapsible and expandable stent extending from an inflowend to an outflow end; a plurality of prosthetic valve leaflets coupledto the stent, each leaflet having a leaflet belly; and a sealing ringcoupled to the inflow end of the stent, the sealing ring comprising atube extending circumferentially around the inflow end of the stent, acovering at least partially surrounding the tube, and at least one of afirst filler positioned within the tube and a second filler positionedbetween the tube and the covering, the sealing ring being axially offsetfrom the leaflet belly when the stent is in a collapsed condition;and/or

the covering is formed from a material selected form the groupconsisting of tissues, fabrics, and polymers; and/or

at least one of the first filler and the second filler is formed from amaterial selected from the group consisting of metals, tissues, fabrics,polymers, and water-swellable materials; and/or

at least one of the first filler and the second filler is configured toexpand upon exposure to blood.

In a further embodiment of the disclosure, a prosthetic heart valvecomprises: a collapsible and expandable stent extending from an inflowend to an outflow end; a plurality of prosthetic valve leaflets coupledto the stent, each leaflet having a leaflet belly; and a sealing ringcoupled to the inflow end of the stent, the sealing ring comprising atube extending circumferentially around the inflow end of the stent anda covering at least partially surrounding the tube, the sealing ringbeing axially offset from the leaflet belly when the stent is in acollapsed condition, wherein the covering has a first edge and a secondedge, the first end coupled to the stent by a first thread; and/or

the first thread couples the first edge of the covering and the tube tothe stent; and/or

a second thread coupling the second edge of the covering to the tube;and/or

the second thread is formed of an elastic material; and/or

the first thread couples the second edge of the covering to the firstedge of the covering and the stent; and/or

the first thread is formed of an elastic material; and/or

the elastic material is silicone.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims. Suchmodification may include, for example, combining of certain elements ofone embodiment of the disclosure with other elements of anotherembodiment of the disclosure.

The invention claimed is:
 1. A prosthetic heart valve comprising: acollapsible and expandable stent extending from an inflow end to anoutflow end; a cuff coupled to the stent; a plurality of prostheticvalve leaflets coupled to the stent; and a sealing ring coupled to theinflow end of the stent, the sealing ring including a tube extendingcircumferentially around the inflow end of the stent and a covering atleast partially surrounding the tube, the covering extending between afirst edge and a second edge that is discontinuous with the first edge,wherein the first edge of the covering is coupled to at least one of thestent and the cuff.
 2. The prosthetic heart valve of claim 1, whereinthe tube is directly coupled to at least one of the stent and the cuff.3. The prosthetic heart valve of claim 2, wherein the second edge of thecovering is coupled directly to none of the tube, the stent, or thecuff.
 4. The prosthetic heart valve of claim 2, wherein the coveringless than fully circumscribes the tube.
 5. The prosthetic heart valve ofclaim 4, wherein a stitch couples both the tube and the first edge ofthe covering to at least one of the stent and the cuff.
 6. Theprosthetic heart valve of claim 1, wherein the second edge of thecovering is coupled directly to the tube.
 7. The prosthetic heart valveof claim 6, wherein the tube is coupled neither directly to the cuff nordirectly to the stent.
 8. The prosthetic heart valve of claim 6, whereina stitch couples both the tube and the first edge of the covering to atleast one of the stent and the cuff.
 9. A prosthetic heart valvecomprising: a collapsible and expandable stent extending from an inflowend to an outflow end; a cuff coupled to the stent; a plurality ofprosthetic valve leaflets coupled to the stent; and a sealing ringcoupled to the inflow end of the stent, the sealing ring including atube extending circumferentially around the inflow end of the stent anda covering at least partially surrounding the tube, the coveringextending between a first edge and a second edge, wherein the first edgeof the covering is coupled to at least one of the stent and the cuff,and wherein the covering fully circumscribes the tube.
 10. Theprosthetic heart valve of claim 9, wherein a stitch couples the firstand second edges of the covering directly to at least one of the stentand the cuff.
 11. The prosthetic heart valve of claim 10, wherein thetube is directly coupled to none of the covering, the stent, and thecuff.
 12. The prosthetic heart valve of claim 10, wherein the stitchalso couples the tube to at least one of the stent and the cuff.
 13. Theprosthetic heart valve of claim 10, wherein an edge of the stent ispositioned between the first edge of the covering and the second edge ofthe covering.
 14. A prosthetic heart valve comprising: a collapsible andexpandable stent extending from an inflow end to an outflow end; a cuffcoupled to the stent; a plurality of prosthetic valve leaflets coupledto the stent; and a sealing ring coupled to the inflow end of the stent,the sealing ring including a tube extending circumferentially around theinflow end of the stent and a covering at least partially surroundingthe tube, the covering extending between a first edge and a second edge,wherein the first edge of the covering is coupled to at least one of thestent and the cuff, and wherein the sealing ring further comprises anouter filler material disposed between the covering and the tube. 15.The prosthetic heart valve of claim 14, wherein the sealing ring furthercomprises an inner filler material disposed within the tube.
 16. Theprosthetic heart valve of claim 14, wherein the outer filler material isformed of a water-swellable material.
 17. The prosthetic heart valve ofclaim 14, wherein the outer filler material is formed of a materialconfigured to expand after exposure to body temperatures.
 18. Aprosthetic heart valve comprising: a collapsible and expandable stentextending from an inflow end to an outflow end; a cuff coupled to thestent; a plurality of prosthetic valve leaflets coupled to the stent;and a sealing ring coupled to the inflow end of the stent, the sealingring including a tube extending circumferentially around the inflow endof the stent and a covering at least partially surrounding the tube, thecovering extending between a first edge and a second edge, wherein thefirst edge of the covering is coupled to at least one of the stent andthe cuff; and wherein the sealing ring further comprises an inner fillermaterial disposed within the tube.
 19. The prosthetic heart valve ofclaim 18, wherein the inner filler material is formed of awater-swellable material.
 20. The prosthetic heart valve of claim 18,wherein the inner filler material is formed of a material configured toexpand after exposure to body temperatures.